[Retracted] Study on Dynamic Evolution of Overburden Rock Movement and Mining-Induced Stress of Ultra-high Working Face

Table 1

Physical and mechanical parameters of coal and rock.

Name	Elastic Modulus (GPa)	Poisson’s ratio	Tensile strength (MPa)	Compressive strength (MPa)
Main roof	30.943	0.27	7.14	25.55
Immediate roof	40.313	0.23	6.28	14.25
Coal	23.872	0.25	2.1	11.68
Floor	47.350	0.22	6.77	22.05